Advantages of stroking a 302
06-05-2003, 03:56 PM
#2
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Advantages of stroking a 302
I'm not a total expert here but first of all I don't think you want to overbore a 302 .060's. They are thin wall blocks and don't have much extra material around the bores. Why .060 and not .020 or .030? Anyway, a 331 uses a 3.25" stroke crank(and .030 overbore) and will gain you HP and torque(maybe 30/40 HP) simply because of the cubic inch increase. The downside is you have to have longer rods and potentially clearance the block for the longer stroke. My feeling is if you are N/A then the increase is worth it but being blown or turbocharged the 302 can make big time power without the increase in cubes. If it's cubic inches you're after go with a stroked 351 Windsor out to 426 inches. That would be a noticable increase.
06-05-2003, 07:01 PM
#4
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Advantages of stroking a 302
Bore= more towards higher RPM's. You don't increase the piston speed, but pull more cfm's at a higher velocity and make more power that way
Stroke= low/mid RPM's is what it's aimed at. Increased piston speed, higher compression, and more pressure on the bearings.
I'd do both, personally (to a 351W).
Stroke= low/mid RPM's is what it's aimed at. Increased piston speed, higher compression, and more pressure on the bearings.
I'd do both, personally (to a 351W).
06-05-2003, 07:26 PM
#5
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Advantages of stroking a 302
Blownvert is correct. If you go .060 over on a Ford small block it better be a race only block filled with block filler. You will thin the walls out so much that you could crack the wall where a water jacket is.
I recommend only .030 over leaving .010 in case there is a problem. Another issue with 347's is the rod ratio. Its a good race motor, but because of its design the motor may only last 60,000 miles if its a daily driven street motor. And like Jeep said, the oil ring has to be run thru a grove in the piston ring leading to leakdown. Another thing to remember is if you go near 500 hp you might want to think of getting an old A4 or new R4 block. The stock 2 bolt main 5.0 is known to litteraly split in half above 500 hp.
I recommend only .030 over leaving .010 in case there is a problem. Another issue with 347's is the rod ratio. Its a good race motor, but because of its design the motor may only last 60,000 miles if its a daily driven street motor. And like Jeep said, the oil ring has to be run thru a grove in the piston ring leading to leakdown. Another thing to remember is if you go near 500 hp you might want to think of getting an old A4 or new R4 block. The stock 2 bolt main 5.0 is known to litteraly split in half above 500 hp.
06-05-2003, 08:25 PM
#7
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Advantages of stroking a 302
Just a quick comment about block strength. The stock forged piston 302 motors can withstand quite a bit of horsepower. Remember the key to making them live is keeping detonation at bay and RPM reasonable (below 6K). If someone grenades a block I'll bet money something crazy happened like over-revving or detonation kicked in. You start surpassing 600 horse, you need to be concerned. If you make that kind of power, another grand or two isn't much compared to the other engines investments.
06-05-2003, 10:14 PM
#9
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Advantages of stroking a 302
Or you could go with the 351 Windsor. I've seen them making 700 horsepower with the stock 2 bolt main blocks. Although I am curious what it sounds like when the crank actually comes out of the block...